Answer: There are many sources of light, but the initial energy for all light sources comes from the sun. Light travels away from its source in straight lines through space as waves of energy. The waves we can detect with our eyes are called visible light. Patterns in the behavior of light are predictable because light moves in waves through space until it comes in contact with an object or material that changes its direction. Light can pass through or bounce off objects. Additionally, different materials can block or absorb light. If an object blocks light, a shadow of the object forms. If the intensity or direction of the light source changes, the appearance of an object’s shadow can change in size, shape, or darkness. Absorbing light energy can cause changes in matter. A common example includes the color of paper or fabric fading as the matter absorbs light over time. Vibrations cause sounds. We can hear when sound waves travel through the air to our ears and cause our eardrums to vibrate. Sound can also travel through other forms of matter, such as liquids and solids.
